IEEE Trans Biomed Eng. 2019 May;66(5):1361-1371. doi: 10.1109/TBME.2018.2872913. Epub 2018 Oct 1.
The aim of this paper is to improve the reconstruction accuracy in both position and source region of fluorescence molecular tomography (FMT).
The reconstruction of the FMT is challenging due to its serious ill-posedness and ill-condition. Currently, to obtain the fluorescent sources accurately, more a priori information of the fluorescent sources is utilized and more efficient and practical methods are proposed. In this paper, we took the group sparsity of the fluorescent sources as a new type of priori information in the FMT, and proposed the fused LASSO method (FLM) for FMT. The FLM based on group sparsity prior not only takes advantage of the sparsity of the fluorescent sources, but also utilizes the structure of the sources, thus making the reconstruction results more accuracy and morphologically similar to the sources. To further improve the reconstruction efficiency, we adopt Nesterov's method to solve the FLM.
Both heterogeneous numerical simulation experiments and in vivo mouse experiments were carried out to verify the property of the FLM. The results have verified the superiority of the FLM over conventional methods in tumor detection and tumor morphological reconstruction. Furthermore, the in vivo experiments had demonstrated that the FLM has great potential in preclinical application of the FMT.
The reconstruction method based on group sparsity prior has a great potential in the FMT study, it can further improve the reconstruction quality, which has practical significance in preclinical research.
本文旨在提高荧光分子断层成像(FMT)中荧光源位置和源区域的重建精度。
由于 FMT 具有严重的不适定性和病态,其重建具有挑战性。目前,为了更准确地获取荧光源,更多地利用了荧光源的先验信息,并提出了更高效、更实用的方法。本文将荧光源的组稀疏性作为 FMT 的一种新的先验信息,提出了用于 FMT 的融合 LASSO 方法(FLM)。基于组稀疏性先验的 FLM 不仅利用了荧光源的稀疏性,还利用了源的结构,从而使重建结果更准确,与源的形态更相似。为了进一步提高重建效率,我们采用 Nesterov 方法来求解 FLM。
通过非均匀数值模拟实验和体内小鼠实验验证了 FLM 的性能。结果验证了 FLM 在肿瘤检测和肿瘤形态重建方面优于传统方法的优越性。此外,体内实验表明,FLM 在 FMT 的临床前应用中具有很大的潜力。
基于组稀疏性先验的重建方法在 FMT 研究中具有很大的潜力,它可以进一步提高重建质量,在临床前研究中具有实际意义。